1. Field of the Invention
This invention relates to a matrix composite for forming a microemulsion of an active ingredient in water, and, more particularly, to a synergistic matrix composite of defined first and second matrix compositions for loading a higher amount of said active ingredient than either composition alone.
2. Description of the Prior Art
The art has described microemulsion concentrates for an active ingredient. See Narayanan U.S. Pat. No. 6,045,816—issued Apr. 4, 2000 “Water-Based Microemulsion of a Pyrethroid” (Microflex®); U.S. Pat. No. 6,187,715—issued Feb. 13, 2001 “Water Based Microemulsions of a Lower Alkyl Ester of Quinoxalinyl Herbicide”; Narayanan U.S. Pat. No. 6,251,416—issued Jun. 26, 2001 “Water-Based Microemulsion of a Pyrethroid” (Microflex®)—covers the concentrates; Narayanan U.S. Pat. No. 6,541,516—issued Apr. 1, 2003 “Water Miscible Emulsions of Pyrethroid Insecticides or Triazole Fungicides”: extension of Microflex using hydrophobic solvents for better stability on dilution.
The co-pending U.S. patent application cross-referenced above contains a defined matrix composition which is effective in forming microemulsions of active ingredients. However, it is desired to provide new and improved synergistic matrix composites for loading higher amounts of active in a stable microemulsifiable form in water than either composition alone.
Most active ingredients, e.g. bioactive materials, are hydrophobic organic compounds with complex structures with very little water solubility. In most applications, the bioactive materials are dispersed in water. The bio-efficacy depends on how finely the bioactive materials are dispersed prior to application on the target organism. Typical formulations of bioactive materials contain either solvents with emulsifiers or polymeric dispersants and stabilizers to formulate concentrates. The concentrates upon dilution in water produce either emulsion droplets or particulate fine dispersions. It is desirable to have the particle size distribution at <2 microns for good biological efficacy. Many solvents and/or emulsifiers have several disadvantages of being either volatile, flammable, irritating, possess aquatic toxicity, and may cause environmental issues from run off.